i use electrolysis only when i have a heavily rusted item, and i can be right there to keep an eye on it, because of the hazards. I have children, pets and neighbors kids who visit my children. My friend Coleen Sloan taught me a method using alfalfa and apple cider vinegar that works real well. The best part is it works and i have fortification to add to my garden after the process because the process ferments the alfalfa.
Get a large plastic tub and put enough alfalfa to make a layer 1 1/2" to 2" deep. place the cast iron on top of the alfalfa (hay, pellets, or cubes) then fill the tub up with more alfalfa to cover the cast iron by 1" minimum. dont forget to put alfalfa inside too. Bring enough water to fill the tub over the alfalfa to a simmer, and at a ratio of 1 part apple cider vinegar to 3 parts of water. Pour the cider vinegar into the tub then the hot water. Let everything soak over night and the next day rinse off the alfalfa and use an SOS pad to scrub the iron. Rinse with HOT water and towel dry then finish drying in the oven and season.
If you have heavy rust put the iron back in the alfalfa solution and soak another night. After scrubbing the iron and drying it, there may be a light orange rust over the iron. This is ok and normal, there is no problem seasoning right over this very light layer of rust.
When im done with the alfalfa, throw it in the garden or trash after 48 hours, it goes into the garden to amend the soil. This stuff stinks when wet after 48 hours because of the chemical reaction between the vinegar and alfalfa.
many people suggest using Coke to remove the rust. It is expensive! it takes at least 4 bottles to cover a frying pan and 6 bottles to cover a 12" Dutch oven. The Coke soak also attracts ants and is very slow.
if you like the idea of electrolysis here are a couple other links to other sites with more pictures. idos Griswold/WAGS
The griswold site really has the best info. in my opinion.